Upwelling Of Numerical Study Of Changjiang River Estuary And Its Adjacent Sea Area In Summer

The coastal waters of the China sea are believed to be a typical upwelling region. Bohai Sea,Yelow Sea,East China Sea Shelf,Taiwan Straits and South China coastal sea also have most upwelling area. Upwelling signals often appear with cold waters. For example,in the upwelling area of Changjiang River Estuary and the coast of Zhejiang,red tides have occured frequently several years in a row,now it is become one of the highest frequency red tide occurrence in China. Because the upwelling can make for mass transport to across continential shelf,take bottom nutritions to euphotic layer,so it can accelerate the growth of phytoplankton and supply positive effects to tide bloom. At the same time,upwelling also is important dynamical environment to the form of ocean fishery. So the studies of upwelling is very important.Based on ECOMSED model, a research has done to analysis the dynamic mechanisms of the upwelling of Changjiang River Estuary and its adjacent sea area in summer. In order to improve the veracity and reliability of upwelling of simulation of CRE and its adjacent sea area,the impacts of river flow,wind, circulation,heat flux and tides(including M2,S2,K1,O1) are taken into account,and through comparisons between every control test to analysis the dynamic mechanisms. The basic model is referred to as the Control Run. In each experiment,a single physical process is closed,and the model is integrated to a quasi-steady state. The effects of this factor are examined by comparing the results of the experiment with that of the Control Run. For the other three cases,the effects of river flow,wind,circulation,heat flux and tides are removed respectively,while keeping other physical processes intact.The result of simulation suggest that the upwelling is mainly induced by the effect of Ekman effect caused by Taiwan Warm Current and rise by continental slope. The study also suggest that tide can affect the upwelling too,but the effect of tides in the upwelling area that we study is not very important.